[crankshaft] Make infinite loop preserve control flow.

test/mjsunit/regress/regress-599710.js

+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+var f1 = function() { while (1) { } }
+
+function g1() {
+  var s = "hey";
+  f1 = function() { return true; }
+  if (f1()) { return s; }
+}
+
+%OptimizeFunctionOnNextCall(g1);
+assertEquals("hey", g1());
+
+var f2 = function() { do { } while (1); }
+
+function g2() {
+  var s = "hey";
+  f2 = function() { return true; }
+  if (f2()) { return s; }
+}
+
+%OptimizeFunctionOnNextCall(g2);
+assertEquals("hey", g2());
+
+var f3 = function() { for (;;); }
+
+function g3() {
+  var s = "hey";
+  f3 = function() { return true; }
+  if (f3()) { return s; }
+}
+
+%OptimizeFunctionOnNextCall(g3);
+assertEquals("hey", g3());
+
+var f4 = function() { for (;;); }
+
+function g4() {
+  var s = "hey";
+  f4 = function() { return true; }
+  while (f4()) { return s; }
+}
+
+%OptimizeFunctionOnNextCall(g4);
+assertEquals("hey", g4());